One object of the present invention is to reduce the damage done to signs and their corresponding sign posts when the signs are mounted for viewing alongside roadways and highways and are suspended from a sign post which is mounted to a concrete or other roadway barrier. Typically, damage may occur when the sign or signpost is struck by snow thrown by a snowplough or is struck by the snowplough blade itself. This problem is recognized in the prior art and applicant is aware of various patent references which attempt to address the problem.
For example, as stated by Shirley in his U.S. Pat. No. 4,205,472, which issued Jun. 3, 1980 for his Yieldable Delayed Action Roadway and Signing Apparatus, on vehicle roadways, particularly in areas where roadways are covered with snow for a part of the year, a continuing problem is the damage and destruction of highway signs and delineators situated at the side of the road for the guidance and warning of passing motorists. Of necessity such signs and delineators must be in close proximity to the roadway so that they can be readily observed by passing motorists. Because of their proximity to the edge of the road they are subject to damage by weed mowers and snowploughs and occasionally by automobiles. In the winter months when the roadways and adjacent areas are covered with snow it is quite easy for snowplough operators to accidentally damage or ruin signs at the side of the road. They must remove enough snow to uncover the roadway and in doing so in deep snow they are likely to remove snow from too wide a path and run into the roadside marker. Mowers also do accidental damage frequently.
A number of attempts have been made by workers in the prior art to find solutions to this problem and solutions have been advanced. They may take the form of a flexible post which by some means can be pushed over and after being passed over by the snowplough spring back up to its original position. However, these ideas may not have been widely adopted because the devices are almost as susceptible to injury as the original posts. Although they theoretically have resilient properties and can spring back to their original position after having been knocked over, in practice the snowplough can completely uproot such posts or sever them or otherwise irreparably damage them.
What Shirley provides is a sign standard which is positioned a safe distance from the roadway to avoid snowploughs, etc. A horizontal movable arm extends from the standard towards the roadway. A sign is carried at the free end of the arm suspended from the arm by the hinges so that the sign can yield when struck. The arm is rotatably mounted on the standard so that the arm and sign may be moved aside if struck. The standard is mounted into the ground. The base end of the arm is mounted into a sleeve in the upper end of the standard. A spring urges the arm to its undeflected position where the arm seats in a notch.
Applicant is also aware of U.S. Pat. No. 3,085,546 which issued to Pelletier on Apr. 16, 1963 for a Traffic Sign. Pelletier describes that an object of this invention resides in providing a traffic sign having means for preventing damage by a motor vehicle when struck by the motor vehicle or other moving objects, for example, when traffic signs are buried in snow and are struck by snowploughs, snowblowers, and the like on highways. Pelletier describes a sign panel which is supported by a horizontal arm which can swing in a vertical plane at right angles to the long axis of the arm so as to clear an object hitting the sign above or below its pivotal connection to the arm, so that the sign always returns to its original vertical position after clearing the striking object. Pelletier discloses that the sign is rigidly secured to an elongate plate like bracket and that the sign is elastically maintained in a vertical plane by means of a coil spring. Pelletier states that if the sign is struck by a moving vehicle or the like, the sign will swing or rotate with respect to the arm to clear the moving object and will return to its vertical position, and depending on the area and force of impact on the sign of the movable object such as a motor vehicle snowplough or the like, either only the sign will rotate with respect to the arm or the arm will pivot with respect to a post on which the arm is mounted, or that there will be a combination of sign rotation and arm pivoting movement. Pelletier observes that his sign is particularly useful in winter time when its frequently happens that road signs are partly or completely buried in snow banks and are very liable to be hit by a snowplough or the like.
Applicant is also aware of U.S. Pat. No. 5,277,146 which issued Jan. 11, 1994, to Hughes Jr., for his Laterally Supported Flexible Sign wherein Hughes states that prior patents have shown yielding roadway signs attached to sign posts by some type of hinge which allows the sign to pivot. Hughes Jr. describes his invention as a rigid sign post where a series of rigid braces are attached to a mounting bracket on the post by a flexible elastomeric sleeve wherein the sign is mounted to the braces. The elastomeric sleeve allows the sleeve and braces to move relative to the sign post after the sign has been hit by a passing object. The sign returns to its original position once the object has passed by.
What is neither taught nor suggested, and what is described herein is a system for mounting a sign and its post to a concrete barrier of the kind placed along side roadways and highways. The post is mounted to minimize damage occasioned by snowploughs and the like striking the base mount of the post where the post is mounted to the concrete barrier. A means is provided for hanging a sign from the upper end of the sign post so that the sign may be deflected and rotated about at least two degrees of freedom when struck by an object such as snow thrown by a snowplough or by the snowplough blade as the road adjacent the concrete barrier is ploughed.